as a guy with a way way over built 454 TBI burb I say swap a junk yard L94 out of an escalade including the whole computer and wiring harness, few grand and a few hard weekends work plus time messing with wiring =403hp & 417ft-lbs, or to get any power out of the TBI the motor needs to be pulled and rebuilt, shaved deck, new full performance heads, cam, push rods, rockers at the least, the throttle body and ignition really limit any top end and the CPU's are untunable so getting a chip burnt is just guess work on how the motor will function but it would do fine for towing, you'll get ~350hp ~400ft-lbs for $4000 as a guess but won't have to mess with wiring
Also a few tips if you do rebuild the 454 in your burb:
1.)don't try and fit long-tube headers on, I have them on mine, not worth it, had to drop the engine in without them, unbolt the passenger side motor mount, hoist the truck, hoist the motor to sit on an angle then pass the passenger header from below. Then had to do it all over again cause their isn't enough room to get a mini-hi torque starter in with them in & its hard to not burn through plug wires
2.)don't put tall valve covers on, they rub the passenger side firewall, I took a hammer drill to a small area on my firewall to give it clearance so it wouldn't pop the valve cover bolts out when I floor it, looks ugly but works